1. Field of the Invention
The present invention relates to a scale system for absolute measurements, including at least one scale which extends along a measuring length and a measuring slide which is movable in relation to the scale, a fine sensor which functions to measure the absolute values within each of the mutually sequential intervals or graduations along the scale, a rough sensor which functions to measure the absolute values with respect to that interval or graduation within which the fine sensor is located at that particular time, and wherein each scale includes scale electrodes which are disposed in a predetermined pattern and which are intended to coact with measuring electrodes mounted at respective measuring heads, wherein a supply voltage is applied to the measuring electrodes to achieve capacitive measuring, and wherein said scale system further comprises a signal includes unit.
2. Description of the Related Art
Systems of this kind are known to the art. However, such known systems are encumbered with serious drawbacks. In known systems which "switch" between two scales that have mutually different graduations, the electrodes must be spaced apart extremely accurately if a comparatively large total measuring length is to be achieved. In other known systems which employ a photoelectric rough scale based on the so-called gray code, it is necessary to use highly complicated measuring heads which need to surround the scale and which include a light-transmitting unit on one side of the scale and a photoreceptive array on the other side thereof. In order to obtain a reasonable scale length, some known systems also require a measuring slide which has a long axial extension in the direction of movement of the slide.